1. Field of the Invention
The present invention relates to a method for controlling operation of an excavator and, more particularly, to a method for automatically controlling the speed ratio of swing and boom operation of the excavator, which makes the operator perform a digging operation in an easy manner.
2. Description of the Prior Art
A conventional excavator includes, as shown in attached drawing FIG. 3, a boom 1 coupled to the main body, a dipper 2 connected with the boom 1 by a rotating pin, and a bucket 3 coupled to the dipper. Further, there is provided a boom cylinder 4 to couple the boom 1 with the main body. Also, a dipper cylinder 5 is provided to couple the dipper 2 with the boom 1 and a bucket cylinder 6 to couple the bucket with the dipper 2. The cylinders 4, 5, and 6 have pistons for moving the boom 1, the dipper 2, and the bucket 3.
The operation of the excavator is performed by manipulating control levers or joy sticks so that the respective fluid valves controlling the movement of the boom 1, the dipper 2, and the bucket 3 and the rotation of the main body may be controlled to move each cylinder piston in accordance with the quantitative displacement of the fluid (the movement of the operating oil) provided at both sides of each cylinders 4, 5, and 6.
With the enhanced reliability of the electronic components and as the technology regarding sensors has developed, a new field of art called mechatronics is applied throughout the industrial machine.
As such technology is applicable to heavy equipment, an attempt has been made to generalize the application of electronic control to an excavator, a crane, a bulldozer and so forth, in the form of the hydronics which is the combination of hydrodynamics and electronics.
Despite the fact that the most popular equipment is the excavator, its usage is relatively more difficult than that of the other equipments, which results in a shortage of skilled operator for the excavator.
Therefore, with the application of electronic control to the conventional hydraulic excavator, by using microprocessors, electromagnetic proportional valves, and electronic sensors, it becomes possible to operate the excavator in an easy and speedy manner even if it is operated by an unskilled operator.
Especially, when the operator runs the excavator of the conventional type to perform a digging operation to manipulate the bucket of the excavator to dig up the earth and place it into a dump truck, the digging operation proceeds depending upon the experience of the operator by manipulating four joy sticks for controlling the swing of the main body and the movement of the boom, the dipper and the bucket.
Such a digging operation continuously performed by a manual operation, is boring and ineffective for the unskilled operator. To solve this problem, it is also proposed that the above-mentioned electronic control be incorporated into the conventional excavator.